Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0149871 (deep vein thrombosis)
 12,364 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Heparin remains the most effective antithrombotic drug. It acts by combining with plasma antithrombin, thereby accelerating the neurtalisation of thrombin and other acitvated coagulation factors. Full-dose intravenous heparin is indicated in all cases of pulmonary embolism and established deep venous thrombosis, unless there exist compelling contraindications. Continuous intravenous infusion of heparin appears to be safer than intermittent injection. Low-dose subcutaneous heparin is effective in preventing the initial occurrence of thigh vein thrombi and in reducing the incidence of fatal pulmonary embolism in general surgical patients over the age of 40. The efficacy of low-dose heparin in preventing pulmonary emboli following hip surgery has not been established. The incidence of severe heparin-induced thrombocytopenia appears to be rising. Platelet counts should be performed in all patients receiving heparin by any mode of administration.
 ...
PMID:Heparin Therapy: regimens and management. 31 90

Most people who experience venous thrombosis have normal hemostasis. Some people have inherited deficiencies of protein C, protein S, and antithrombin iii. They tend to have deep venous thrombosis which increases their risk for pulmonary emboli. Some acquired disorders which predisposes people to thrombosis include defective fibrinolysis which often occurs after surgery or infection, Trousseau's syndrome (excessive coagulant activity linked with adenocarcinoma), and lupus anticoagulant which is an immunoglobulin G or M antibody directed against negatively charged phospholipids. Hormones and probably not a dilution effect reduces free and bound protein S levels during pregnancy. Functional protein S activity is still 40-50% below normal levels 1-3 days after delivery. This decrease appears to protect against bleeding but does have venous thrombosis and pulmonary emboli during pregnancy as side effects. Non-oral-contraceptive (OC) users have greatly higher protein S levels than do OC users (28.6 mcg/ml vs. 24.3 mcg/ml; p.005) which gives more credence to the belief that hormones are responsible for the fall in protein S activity during pregnancy. OCs reduce free and total protein S levels almost 20%. Smoking may even further reduce these levels in women during pregnancy and who use Ocs. Women who have had venous thrombosis should not use OCs. Physicians should also consider family history especially age of affected family member, severity of thrombotic episodes, and the clinical setting. They should look for an underlying abnormality in patients who develop thrombosis while using OCs. If thrombosis develops during pregnancy, physicians should call for a venogram, venous duplex scanning, and, if required, invasive tests. The most sensible treatment is intravenous heparin for 5-7 days then therapeutic doses of heparin. Heparin therapy should stop before delivery and be reinstituted shortly thereafter and continued throughout the postpartum period. Physicians should take extra precautions when performing surgery on an OC user.
 ...
PMID:Recent advances in understanding clotting and evaluating patients with recurrent thrombosis. 141 44

The D-Dimer (D-D) assay for measuring cross-linked fibrin degradation products is now available for the clinical laboratory. We combined this assay with other tests to assess patients with diagnosed or suspected DIC. Also, a small group of patients (20) with deep venous thrombosis (DVT) were studied. The D-D test, antithrombin-III assay, FDP titer, fibrinopeptide-A level, protamine sulfate test, fibrinogen, prothrombin time, and activated partial thromboplastin time were used. The D-D test was abnormal in 93.7%, the AT-III level was abnormal in 87.5%, the fibrinopeptide-A level was abnormal in 89.5%, and the FDP titer was elevated in 83.7% of patients with DIC. When assessing patients found not to have confirmed DIC the D-D assay was abnormal in 20%, the AT-III level was abnormal in 6%, and the fibrinopeptide-A level was elevated in 13%. We conclude the D-Dimer assay to be a useful molecular marker of hemostasis in diagnosing DIC and this test will often discriminate between those patients with or without DIC, especially when used with the AT-III and fibrinopeptide-A assays. Of the battery of tests used in this study, the most useful, in descending order of efficacy, appear to be the D-dimer assay (93.7% abnormal), the fibrinopeptide-A titer (89.5% abnormal), the AT-III level (87.5% abnormal), and the FDP titer (83.7% abnormal). Of the global tests, the diagnostic efficacy of the prothrombin time activated partial thromboplastin time, and protamine sulfate test were no greater than chance and appear to be of little use in aiding in a diagnosis of DIC. Also, the D-Dimer assay is similar in cost to the FDP titer and is cost effective for the routine clinical laboratory.
 ...
PMID:Diagnostic efficacy of the D-dimer assay in disseminated intravascular coagulation (DIC). 163 67

The depolymerisation of the various chains of unfractionated heparin (UFH) by chemical or enzymatic reactions provides so-called low molecular weight heparin (LMWH), with an average molecular weight of approximately 5000 daltons. The specific biological and pharmacokinetic properties of LMWH with greater inhibition of factor Xa than of thrombin activity, less interaction with platelets, better bioavailability and a longer half life of anti-Xa activity, suggest possible new therapeutic applications. The hypothesis of reducing the risk of haemorrhage related to the antithrombin activity and the incidence of heparin-induced thrombocytopenia whilst preserving effective antithrombotic action has stimulated clinical and biological research. Clinical trials of prophylaxis of venous thrombo-embolism have been undertaken mainly in surgical patients. The results have shown identical if not better efficacy of LMWH compared to UFH in general surgical and above all orthopedic patients in whom subcutaneous heparin is only effective with a strict protocol which is difficult to adhere to in routine practice (adaptation of dosage to activated partial thromboplastin time). The risk of bleeding was not significantly lower using LMWH at the specified dosage, which in the latter indication, is twice that used in general surgery. There are many indications of prophylaxis of thromboembolism in the medical specialties but, paradoxically, LMWH has not been widely studied because of the difficulties in performing the therapeutic trials. Except in rare cases (extreme body weights, renal failure, haemorrhagic disease, thrombotic or haemorrhagic complications) the evaluation of amidolytic anti-Xa activity does not seem to be necessary. More recently, LMWH has been studied in a small number of trials for the treatment of deep venous thrombosis (DVT). The therapeutic efficacy is identical if not better than that of UFH without increasing the risk of bleeding. Biological monitoring seems to be necessary in this indication for evaluating amidolytic anti-Xa activity, which, though not a true marker of antithrombotic activity is a relatively sensitive investigation. The therapeutic values are 0.5 IU/ml to 1.0 IU/ml, 3 to 4 hours after subcutaneous injection. The conclusions of all these trials are: LMWH is relatively simple to use and, compared with UFH, has a more stable anticoagulant effect due to its pharmacokinetic properties; the therapeutic efficacy is as good as, if not better, than that of UFH; the risk of bleeding remains, therefore, the specified dosages should be respected and treatment should be monitored by anti-Xa activity when indicated; the decreased interaction with platelet function should not mask the risk of thrombocytopoenia.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:[Therapeutic indications of low molecular weight heparins]. 166 41

In a prospective randomized study heptest, thrombin-antithrombin complexes (TAT), D-dimer, and t-PA:ag were analysed pre- and postoperatively in 206 consecutive patients undergoing hip arthroplasty during thromboprophylaxis with either a LMW heparin (Enoxaparin) or Dextran 70. Deep vein thrombosis (DVT) developed in 6 of 102 (6%) Enoxaparin and in 21 of 104 (20%) Dextran patients diagnosed by bilateral phelobography. In the Enoxaparin group heptest showed a significant increase from the pre- to the postoperative level opposed to a significant decrease in the Dextran group. Postoperative levels of TAT, D-dimer, and t-PA:ag were significantly increased in both groups, however, TAT was significantly higher in patients in the Dextran group than in the Enoxaparin patients. D-dimer was significantly higher in Dextran patients with DVT postoperatively compared with patients without DVT. No differences concerning TAT or t-PA:ag were observed between patients with and without DVT in any of the groups.
 ...
PMID:Components of coagulation and fibrinolysis during thrombosis prophylaxis with a low molecular weight heparin (Enoxaparin) versus Dextran 70 in hip arthroplasty. 171 55

We describe a 43-year-old male patient with congenital antithrombin III deficiency requiring hemodialysis due to extension of venous thrombus from recurrent deep vein thrombosis. During dialysis with adequate heparinization, the patient often revealed clot formation in the extracorporeal circuit resulting in unexpected discontinuation of dialysis. When either a combination of antithrombin III concentrate + heparin or the newly developed synthetic antithrombin preparation, MD805, was administered during dialysis, he could be uneventfully dialyzed with either of the two regimens.
 ...
PMID:Anticoagulant therapy in a congenital antithrombin III (ATIII)-deficient patient with chronic renal failure undergoing regular hemodialysis. 175 68

In a randomized doubled-blind placebo-controlled study, plasma levels of thrombin-antithrombin-III (TAT) and factor VIII activity (VIII:C) were measured pre-operatively and on days 1, 3, 5 and 7 post-operatively in 70 consecutive patients undergoing total hip replacement. Patients received either a subcutaneous injection of low-molecular-weight heparin (LMWH) or placebo once daily. Post-operative deep vein thrombosis (DVT) was diagnosed by bilateral phlebography. The levels of TAT and VIII:C both increased significantly after operation and were not significantly influenced by LMWH. Thirty-three patients in whom post-operative DVT developed had a significantly lower level of VIII:C on day 7, compared with patients without DVT.
 ...
PMID:Levels of thrombin--antithrombin-III complex and factor VIII activity in relation to post-operative deep vein thrombosis and influence of prophylaxis with a low-molecular-weight heparin. 196 94

Broad spectrum assays which measure a range of fibrinogen/fibrin derivatives (FDPs) in serum have become an established means of identifying activation of blood coagulation and/or fibrinolysis, such as occurs in disseminated intravascular coagulation (DIC). There is considerable interest in the application of these assays to the diagnosis of other hypercoagulable states, such as recurrent deep venous thrombosis and myocardial infarction. In recent years, more sensitive and specific FDP assays (e.g. for fragment E, fragment E neoantigen, D-dimer, fragment D neoantigen, fibrinopeptide A and fibrin fragment beta 15-42) have been devised, some of which allow measurement in plasma of FDPs without interference from fibrinogen or certain of its derivatives. It was predicted that these assays would both avoid the possibility of artifacts introduced as a consequence of serum preparation and improve detection of hypercoagulable states. In the light of these expectations we have reviewed data published on the use of assays to detect clinical hypercoagulability, giving prominence to assays of crosslinked fibrin derivatives and nothing particularly certain studies that have compared the performance of different assays on the same samples. The accumulating evidence indicates that all of the assays are adequate for detection of DIC. The same cannot be said for other hypercoagulable states. Here much variation is evident between different studies of similar patients in the ability of a particular marker to discriminate between a normal control group and patients determined to be hypercoagulable by an independent method. This variability would seem to be a function of patient group heterogeneity and selection, as assays that detect different antigenic determinants produce results on the same plasma samples that are well correlated. It appears that the precise antigenic determinant does not critically affect detection of hypercoagulability. Additionally, some studies have indicated that use of serum need not introduce artifacts. Despite there being no other obvious advantage, the convenience of some of the plasma assays may well encourage their widespread use. Assays have also been developed for measuring activation fragments of coagulation proteins (e.g. prothrombin fragment F1 + 2 and protein C activation peptide) and for proteinase inhibitor complexes (e.g. thrombin-antithrombin complex) generated during activation of coagulation. The latter assays have been useful in providing a biochemical definition of a 'prethrombotic state'.
 ...
PMID:Assessment of hypercoagulable states by measurement of activation fragments and peptides. 218 46

Measurements were made of levels of D-dimer in plasma and serum, thrombin-antithrombin complex (TAT) in plasma and fibrinogen/fibrin fragment E antigen (FgE) in serum in a normal healthy control group and in patients with a range of disorders associated with hypercoagulability. Levels were determined in 31 normal healthy controls, 30 patients with disseminated intravascular coagulation (DIC), 21 patients with deep venous thrombosis (DVT), 27 patients with myocardial infarction (MI), 26 patients with acute leukaemia and 56 patients with liver disease. Considering all subjects, significant correlations were established between the results of all assays. Notably high correlations (r greater than 0.9) were established between plasma and serum levels of D-dimer, between plasma levels of D-dimer and serum levels of FgE, and between serum levels of D-dimer and FgE. All assays showed very high discrimination (sensitivity) between the normal control group and patients with DIC (97-100%), but there were marked differences between the assays in sensitivity for DVT and MI. In general, the FgE assay was more sensitive than the D-dimer assay, whilst both the FgE and D-dimer assays were more sensitive than the TAT assay. The same trends were apparent in the capability of the assays to discriminate between the normal control group and patients with acute leukaemia and liver disease: disorders with an unknown prevalence of activation of coagulation/fibrinolysis. Our results indicated that measurements of fibrinogen/fibrin degradation products (FDPs) in serum were almost unaffected by artefacts. The data further suggested that the broad-spectrum FgE assay was better than the more specific D-dimer assay in detecting clinical hypercoagulability. Our study showed that, in the clinical conditions examined, FDPs were more effective markers of hypercoagulability than TAT.
 ...
PMID:A comparative evaluation of assays for markers of activated coagulation and/or fibrinolysis: thrombin-antithrombin complex, D-dimer and fibrinogen/fibrin fragment E antigen. 218 90

Thrombin-antithrombin-III complexes (TAT) & D-dimer in plasma, and fibrin(ogen) degradation products (FDP) in serum, were measured in 48 patients subjected to total hip arthroplasty. Blood samples were collected on days -1, 0, 1, 3, 7 and 10. Five patients developed postoperative deep vein thrombosis (DVT) diagnosed by venography. A characteristic pattern of TAT and D-dimer secondary to surgery was demonstrated. A poor correlation was found between ELISA- and latex-D-dimer concentrations after the operation. Patients with DVT had significantly higher TAT-levels preoperatively, and on day 0, 7 and 10. The concentration of FDP was significantly elevated in patients with DVT on day 7 and that of ELISA D-dimer on days 0 & 10. None of the assays are clinically valuable for purposes of postoperative screening for DVT. The preoperative plasma TAT concentration may represent a valuable predictive marker of postoperative DVT.
 ...
PMID:Thrombin-antithrombin III-complex & fibrin degradation products in plasma: surgery and postoperative deep venous thrombosis. 220 19


1 2 3 4 5 6 7 8 9 10 Next >>